@georgepenney This never happens to me, because I never use the automatic checkout.
It's not just that it's a machine that's replacing humans - but I once got dinged by a checker because I accidentally took 5 croissants instead of 4 (€0.25 cents each) because two were stuck together and I realized that one slip on my part could be a theft charge.
There in .nl, uptake was originally high but seems to have decreased dramatically.
Here in France they're worse... I never use them.